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Related papers: Effective approach to lepton observables: the sees…

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We analyze lepton flavor violation (LFV) using the Standard Model Effective Field Theory (SMEFT) framework at the future lepton colliders. Our focus is on the associated production of tau lepton with electron/muon at the electron-positron…

High Energy Physics - Phenomenology · Physics 2025-05-28 Sahabub Jahedi , Abhik Sarkar

We study a new supersymmetric mechanism for lepton flavour violation in muon and tau decays and muon -> e conversion in nuclei, within a minimal extension of the MSSM with low-mass heavy singlet neutrinos and sneutrinos. We find that the…

High Energy Physics - Phenomenology · Physics 2015-05-13 Amon Ilakovac , Apostolos Pilaftsis

A supersymmetric see-saw model obeying the flavor symmetry L_mu - L_tau, which naturally predicts quasi-degenerate neutrinos, is investigated. Breaking of the symmetry is introduced in the Dirac mass matrix because it is the most economic…

High Energy Physics - Phenomenology · Physics 2010-04-05 Toshihiko Ota , Werner Rodejohann

We study lepton flavor number violating rare B decays, $b \to s l_h^{\pm} l_l^{\mp}$, in a seesaw model with low scale singlet Majorana neutrinos motivated by the resonant leptogenesis scenario. The branching ratios of inclusive decays $ b…

High Energy Physics - Phenomenology · Physics 2009-11-11 T. Fujihara , S. K. Kang , C. S. Kim , D. Kimura , T. Morozumi

We apply the covariant derivative expansion method to integrate out the neutralinos and charginos in the minimal supersymmetric Standard Model. The results are presented as set of pure bosonic dimension-6 operators in the Standard Model…

High Energy Physics - Phenomenology · Physics 2018-05-08 Huayong Han , Ran Huo , Minyuan Jiang , Jing Shu

Within the Standard Model Effective Field Theory framework, with operators up to dimension 6, we perform a model-independent analysis of the lepton-flavour-violating processes involving tau leptons. Namely, we study hadronic tau decays and…

High Energy Physics - Phenomenology · Physics 2021-02-03 Tomas Husek , Kevin Monsalvez-Pozo , Jorge Portoles

Given its briefness and predictability, the minimal seesaw -- a simplified version of the canonical seesaw mechanism with only two right-handed neutrino fields -- has been studied in depth and from many perspectives, and now it is being…

High Energy Physics - Phenomenology · Physics 2021-05-10 Zhi-zhong Xing , Zhen-hua Zhao

These proceedings review the status of present and future bounds on muonic lepton flavour violating transitions in the context of an effective-field theory defined below the electroweak scale. A specific focus is set on the phenomenology of…

High Energy Physics - Phenomenology · Physics 2018-07-02 Giovanni Marco Pruna

Extending the Standard Model with higher-dimensional operators in an effective-field-theory (EFT) approach provides a systematic framework to study new-physics (NP) effects from a bottom-up perspective, as long as the NP scale is…

High Energy Physics - Phenomenology · Physics 2020-01-29 Marzia Bordone , Oscar Catà , Thorsten Feldmann

The Standard Model includes neutrinos as massless particles, but neutrino oscillations showed that neutrinos are not massless. A simple extension of adding gauge singlet fermions to the particle spectrum allows normal Yukawa mass terms for…

High Energy Physics - Phenomenology · Physics 2012-12-24 D. Jurciukonis , T. Gajdosik , A. Juodagalvis , T. Sabonis

New physics not far above the TeV scale should leave a pattern of virtual effects in observables at lower energies. What do these effects tell us about the flavor structure of a UV theory? Within the framework of Standard Model Effective…

High Energy Physics - Phenomenology · Physics 2021-06-16 Sebastian Bruggisser , Ruth Schäfer , Danny van Dyk , Susanne Westhoff

We study the effects of Lepton Flavor Violation (LFV) in the scalar lepton sector of the MSSM on precision observables such as the W-boson mass and the effective weak leptonic mixing angle, and on the Higgs-boson mass predictions. The…

High Energy Physics - Phenomenology · Physics 2024-07-02 M. E. Gómez , T. Hahn , S. Heinemeyer , M. Rehman

This work is based on a bottom{-}up approach to the standard{-}model effective field theory (SMEFT), resulting in an equiprobable space of Wilson coefficients. The randomly generated Wilson coefficients of the SMEFT (in the Warsaw basis)…

High Energy Physics - Phenomenology · Physics 2023-02-08 Federico Camponovo , Giampiero Passarino

The lepton flavour violating (LFV) $\tau$ decays $\tau\to (e,\mu)\gamma$ and $\tau\to 3\mu$ are investigated in the frameworks of the TeV scale type I see-saw and Higgs Triplet (or type II see-saw) models. Predictions for the rates of these…

High Energy Physics - Phenomenology · Physics 2015-06-16 D. N. Dinh , S. T. Petcov

When the standard model is extended with right-handed neutrinos the symmetries of the resulting Lagrangian are enlarged with a new global U(1)R Abelian factor. In the context of minimal seesaw models we analyze the implications of a…

High Energy Physics - Phenomenology · Physics 2015-06-11 D. Aristizabal Sierra

We use unitarity and analyticity of scattering amplitudes to constrain fermionic operators in the standard model effective field theory. For four-fermion operators at mass dimension 8, we scatter flavor superpositions in fixed standard…

High Energy Physics - Phenomenology · Physics 2021-09-02 Grant N. Remmen , Nicholas L. Rodd

We present SUSY_FLAVOR version 2.5 - a Fortran 77 program that calculates low-energy flavor observables in the general $R$-parity conserving MSSM. For a set of MSSM parameters as input, the code gives predictions for: 1. Electric dipole…

High Energy Physics - Phenomenology · Physics 2014-09-29 A. Crivellin , J. Rosiek , P. H. Chankowski , A. Dedes , S. Jager , P. Tanedo

We perform a global analysis of the bounds from charged lepton flavour violating observables to new physics. We parametrize generic new physics through the Effective Field Theory formalism and perform global fits beyond the common…

High Energy Physics - Phenomenology · Physics 2025-10-07 Enrique Fernández-Martínez , Xabier Marcano , Daniel Naredo-Tuero

We study a non-universal flavor scenario at the level of the Standard Model Effective Field Theory, according to which the matrix of Wilson coefficients $c_{uW}$ of an up-type electroweak quark dipole operator is aligned with the up-type…

High Energy Physics - Phenomenology · Physics 2024-11-26 Quentin Bonnefoy , Jonathan Kley , Di Liu , Alejo N. Rossia , Chang-Yuan Yao

For Leptogenesis based on the type-I seesaw mechanism, we present a systematic calculation of lepton-number violating and purely flavoured asymmetries within nonequilibrium Quantum Field Theory. We show that sterile neutrinos with…

High Energy Physics - Phenomenology · Physics 2015-06-05 Marco Drewes , Bjorn Garbrecht